<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            display:grid;
            grid-template-columns:repeat(3,100px);
            grid-template-rows:repeat(3,100px);
            justify-content: center;
            align-content:center;
            /* align-items:flex-end; */
            justify-items: center;
            align-items: center;

        }
        .child {
            border:1px black solid;
        }
    </style>
</head>
<body>
    <div class="box">
        <div class="child">1</div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child">4</div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
        <div class="child"></div>
    </div>
</body>
</html>